DEMO: Demonstrating reactive smartphone-based jamming

Reactive Wi-Fi jammers on off-the-shelf hardware that may facilitate mobile friendly jamming applications have only been shown recently. Until now, no demonstrators existed to reproduce the results obtained with these systems, hence, inhibiting re-use for further research or educational applications. In this work, we present an Android app that allows to create advanced jamming scenarios with four Nexus 5 smartphones. We use two of them to inject Wi-Fi frames with UDP payload, one to receive frames and analyze if they were corrupted and one that acts as a reactive jammer that selectively jams according to a UDP port. The user can choose between a simple reactive jammer and an acknowledging jammer. All jammers are implemented as Wi-Fi firmware patches by using the Nexmon framework. During the demonstration, users may adjust parameters of transmitted frames and observe the throughputs of correct and corrupted frames as bar graphs at the receiver. At the jamming node, users may design an arbitrary jamming signal in the frequency domain and adjust the jamming power, the target UDP port and the jammer type. The MAC addresses used during the experiments are hard coded to hinder users from simply abusing the app in other setups. Overall, the demonstration proofs that highly sophisticated Wi-Fi jammers can run on smartphones.